Resonance-relay.



PATENTED NGV. 22, 1904.

I No. 775,680.

P. O. PEDERSEN.

RESONANCE RELAY.

APPLICATION FILED JULY 21.1001.

N0 MODEL.

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PATENT OFFICE.

RESONANCE-RELAY.

SPECIFICATION forming part of Letters Patent No. 775,680, dated November 22, 1904.

Application filed July 31, 1901. Serial No. 70,337. (No model.)

To all whom it may concern.-

Be it known that I, PEDER OLUF PEDERSEN, a citizen of the Kingdom of Denmark, residing in Copenhagen, Denmark, have invented certain new and useful Improvements in Relays, of which the following is a specification.

The object of this invention is to provide a highly-sensitive relay having low resistance and self-induction and sensitive only to currents of certain character. For this purpose the invention consists of a relay comprising a pair of oppositely-arranged tuning-forks and vibrators stretched between said forks and located in a magnetic field.

In the accompanying drawings, Figure 1 is a vertical longitudinal section on line 1 1, Fig. 2, of a relay embodying my invention. Fig. 2 is a top view of the relay shown in Fig. 1 with main and local circuits connected therewith, and Fig. 3 is avertical transverse section on line 3 3, Fig. 2.

Similar characters of reference indicate corresponding parts.

Referring to the drawings, A indicates a base-plate upon which are mounted parallel with each other and at a suitable distance apart two vibratory forks A A In order to secure the firm mounting of these relatively to each other, they may be braced by or made integral with a connecting-plate Z). A permanent magnet A is mounted upon the base or plate 5 between the forks. Between the leg 0 of the fork A and the opposite leg 0 of the fork A is located a vibrator-wire d, which traverses the field of the magnet A and between the legs 0 and 0" of said forks is located a vibrator-wire (Z which also traverses said field. Said wires (Z d are not in electric connection with the forks, but are insulated therefrom by blocks of insulating material c c 0 0 mounted on the forks. Any suitable means, such as screws 8 s .9 s on the forks, may be employed for securing the wires. The wires are connected by a conductor (Z and are in circuit with a generator A of current of the same frequency as that of the vibrators of which they form a part. In place of one wire D and one wire 0Z two or more of each may be employed. The sensitiveness of the instrument is increased by increasing the number.

A contact-screw 0 is mounted in one of the forks, preferably in one of the insulatingblocks of the same, as 0, and is adjustable toward and away from an opposite screw memher 0, which is secured reliably in position in the opposite block 0 by means of a jam-nut 0 The screw 0 carries at its outer end a platinum contact-plate 0 and the point of the screw 0 is also preferably shod with platinum and is located opposite said plate 0 and at such distance therefrom that upon the vibration of the fork A contact will be formed between the members 0 The relay is provided with four bindingposts, two for the main circuit and two for the local circuit. From the post 6 of the latter a conductor 42 extends and makes connection with a contact-plate 0 secured by a screw to the inner face of the block 0", said contact-plate bearing frictionally upon the screw 0 From the binding-post 72 conductor 48 extends into connection with screw 0, as shown in Fig. 8. To the binding-posts 7) are connected by conductors 44, 45, and 46 the battery I) and the sounder 6 of the local circuit. From the binding-post b a conductor 47 connects with the vibrator-wire d, and from the bindingpost b a conductor 48 connects with the wire CZ. By means of the conductors 49, 50, and 51 the key cl and generator A of the main line are connected with the wires (Z (Z in such manner that upon depressing the key a current from the generator traverses both.

The operation of this relay is as follows: Upon depressing the key (F the main current, which is of the same period as the period of vibration of both vibrators, passes from the generator A through conductor 50, key (Z*, and successively the parts 49, b, 47 (1, (l cl", 48, 72 and 51 back to the generator. The effect of the current is to throw the vibrators-rl e. the wires d d" and forks A A -into violent vibra tion. The effect of this movement at the fork A is to cause the point of the screw 0 to rapidly make and break contact with the plate 0 thereby permitting a current from the local battery Z)" to flow through the course 44, 42, 0 0 0 o 43, Z). 46, sounder-6 and conductor 45 back to battery 6, whereby the sounder is actuated, said current being substantially continuous, so that the sounder-armature is continuously attracted. Upon raising the key cl the vibrations quickly become so much shorter in length that no contact between 0 and 0 takes place. The local circuit is thereby broken, and the sounder-magnets release the sounder-armature.

The instrument described fulfils the function of a relay in the common sense of that termnamely, as indicating an instrument adapted to close a second or local circuit. It is also adapted for use as a sounder, and when so used the contact devices and local circuit may be entirely omitted. In such case the frequency employed is such as is within the compass of the human ear. Where a contact device and local circuit is employed, however, frequencies of vibration above or below the range of the human car may be employed. The magnetic field being invariable and the direction of the current forces perpendicular to the current as well as to the lines of force of the field the vibrator is affected by forces which are proportionate to the electric current present.

In order to increase the duration of contact, the contact devices may be difierently constructed from those shown, one member consisting of a platinum pin and the other of, for example, a mercury-cup. The contact de vices may also be constructed in accordance with those used by fork-interrupters or other vibrating interrupters.

Having thus described my invention, 1: claim as new and desire to secure by Letters Patent 1. A relay, consisting of a pair of oppositelyarranged tuning-forks, and vibrators stretched between said forks, and located in a magneti c field, substantially as set forth.

2. A relay,consisting of a pair of oppositelytween said forks and located in a magnetic field, and a contact device controlled by one of said tuning-forks, substantially as set forth.

3. A relay, consisting of a pair of oppositelyarranged tuning-forks, and vibrators having each the same period of vibration stretched between said forks and located in a n'iagnetic field, substantially as set forth.

a. A relay,consisting of a pair of oppositelyarranged tuning-forks, vibrators stretched between said tuning-forks and having each the same period of vibration, and a contact device between the members of one of said forks, substantially as set forth.

In testimony that I claim the foregoing as my invention I have signed my name in presence of two subscribing witnesses.

PEDER OLUF PEDERSEN. l/Vitnesses:

HANS (JOLBERG,

Greeo BLoM.

arranged tuning-forks, vibrators stretched be- 

